JP7485778B2 - Vacuum seal device and drive transmission device - Google Patents

Description

The present invention relates to a vacuum seal device and a drive transmission device that transmit rotational power from the outside to the inside of a vacuum chamber while preventing the intrusion of atmospheric air into the vacuum chamber.
This application claims priority to Japanese Patent Application No. 2020-180316, filed in Japan on October 28, 2020, the contents of which are incorporated herein by reference.

In factories that manufacture semiconductor wafers and liquid crystal substrates, etc., particles are undesirable and precise processing is required. For this reason, the operating parts of transport robots and other devices are sometimes placed inside a vacuum chamber (a room with the inside kept in a vacuum state). The rotational power of a drive transmission device is transmitted to the operating parts from outside the vacuum chamber. A drive device such as a motor in the drive transmission device is placed outside the vacuum chamber. The rotation transmission member of the drive transmission device penetrates the partition of the vacuum chamber and is connected to the operating part inside the vacuum chamber. In order to prevent air from entering the inside of the vacuum chamber through the gap between the through hole in the partition of the vacuum chamber and the rotation transmission member, the drive transmission device is equipped with a vacuum seal device (see, for example, Patent Document 1).

The vacuum seal device described in Patent Document 1 comprises a housing, a rotation transmission member, and a direct contact type seal member. The housing is arranged straddling the inside and outside (vacuum side and atmosphere side) of the vacuum chamber. The rotation transmission member transmits rotational power from the atmosphere side to the vacuum side by penetrating the housing. The seal member makes sliding contact with the outer circumferential surface of the rotation transmission member to seal the space between the housing and the rotation transmission member. A cooling passage is formed in the housing so that it faces the outer circumferential surface of the rotation transmission member and the sliding contact portion of the seal member from the atmosphere side. A cooling fluid such as cooling air or cooling liquid flows through the cooling passage.

In the vacuum seal device, when the rotation transmission part is driven, the seal member attached to the housing slides in contact with the outer circumferential surface of the rotation transmission member, thereby preventing the atmosphere from entering the vacuum chamber through the gap between the rotation transmission member and the housing.
The seal member may be deteriorated by heat generated by sliding contact with the rotation transmission member. When the seal member is deteriorated, there is a risk that the sealing performance of the seal member may decrease. For this reason, in the vacuum seal device, a cooling fluid is passed between the outer peripheral surface of the rotation transmission member and the sliding contact portion of the seal member, thereby preventing deterioration of the seal member due to heat generation.

International Publication No. 2007/080986

In the vacuum seal device described in Patent Document 1, a cooling flow path is formed in a position on the atmospheric side of the housing facing the sliding contact portion of the rotation transmission member and the seal member. This makes it difficult for the part of the seal member that is arranged on the vacuum side to be cooled by the cooling fluid. In particular, when the seal members are arranged in multiple stages along the axial direction between the housing and the rotation transmission member, the cooling fluid does not come into contact at all with the seal member that is arranged on the vacuum side. As a result, heat due to sliding contact is likely to remain in part of the seal member.

The present invention provides a vacuum seal device and a drive transmission device that can efficiently remove heat from a sealing member over a wide area spanning from the atmosphere side to the vacuum side of the sealing member.

(1) A vacuum seal device according to one aspect of the present invention comprises a housing arranged to straddle a vacuum side, which is the inside of a vacuum chamber, and an atmosphere side, which is the outside of the vacuum chamber; a rotation transmission member arranged to penetrate the housing and rotate about a central axis to transmit rotational power from the atmosphere side to the vacuum side; and a seal member arranged in sliding contact with an outer peripheral surface of the rotation transmission member to seal between the housing and the rotation transmission member, wherein the housing has a seal support portion that supports the seal member, an outer cooling passage through which a cooling fluid flows is formed in an area of the housing that is located radially outward from the seal support portion , and the housing is provided with an inner cooling passage through which a cooling fluid flows, and the inner cooling passage faces the sliding contact portion of the seal member that contacts the rotation transmission member and the rotation transmission member from the atmosphere side.

With the above configuration, the rotational transmission member receives rotational power from the atmospheric side and transmits the rotational power to the required parts within the vacuum chamber. At this time, a sealed state is maintained between the housing and the rotational transmission member by the seal member. The radially outer area of the seal support part of the housing is cooled by the cooling fluid flowing through the outer cooling passage. Therefore, frictional heat that tends to accumulate at the base of the vacuum side of the seal member can be removed by the cooling fluid flowing through the outer cooling passage.

( 2 ) A liquid may be introduced as the cooling fluid into the outer cooling passage, and a gas may be introduced as the cooling fluid into the inner cooling passage.

( 3 ) The seal member may be arranged in a plurality of pieces along the axial direction of the rotation transmission member between the housing and the rotation transmission member.

( 4 ) The seal member may include a base portion fixed to the seal support portion, an annular seal portion extending radially inward from the base portion and in sliding contact with the outer peripheral surface of the rotation transmission member, and a core metal embedded so as to straddle from the seal portion to the base.

( 5 ) The core metal may be in contact with the housing.

( 6 ) The seal support portion may have an inner circumferential wall facing an outer circumferential surface of the rotation transmission member, and an end wall extending radially inward from one axial end of the inner circumferential wall, and the core metal may be in contact with the end wall.

( 7 ) The housing may include a first housing having a groove opening to one end side in the axial direction, and a second housing closing the opening of the groove and constituting the outer cooling passage together with the groove, and the second housing may include a peripheral wall constituting a part of the inner cooling passage, and a protrusion provided at one end of the peripheral wall and tightly fitted into at least a radially inner surface of the inner surface forming the groove.

( 8 ) A drive transmission device according to one aspect of the present invention comprises a drive unit arranged on the atmosphere side outside a vacuum chamber, and a vacuum seal device that transmits power of the drive unit to a driven part arranged on the vacuum side inside the vacuum chamber and regulates the ingress of atmosphere into the vacuum chamber, the vacuum seal device comprising: a housing arranged across the vacuum side and the atmosphere side of the vacuum chamber; a rotation transmission member arranged to penetrate the housing and rotate around a central axis to transmit rotational power from the drive unit to the driven part; and a seal member arranged in sliding contact with an outer peripheral surface of the rotation transmission member and sealingly sealing between the housing and the rotation transmission member, the housing having a seal support part that supports the seal member, an outer cooling passage through which a cooling fluid flows is formed in an area of the housing located radially outward from the seal support part , and the housing has an inner cooling passage through which a cooling fluid flows, the inner cooling passage facing the sliding contact part of the seal member that contacts the rotation transmission member and the rotation transmission member from the atmosphere side.

In the above-mentioned vacuum seal device, a cooling fluid flows through an outer cooling passage provided in the radially outer region of the seal support part of the housing. This allows heat from the seal member to be efficiently removed over a wide region spanning from the atmospheric side to the vacuum side of the seal member. Therefore, when the above-mentioned vacuum seal device is used, the sealing performance of the seal member is maintained well for a long period of time.

The above-mentioned drive transmission device can efficiently remove heat from the sealing member over a wide area spanning from the atmospheric side to the vacuum side of the sealing member using the vacuum seal device. This allows the power of the drive device to be transmitted to the driven part in the vacuum chamber while maintaining good sealing performance of the sealing member for a long period of time.

1 is a partial cross-sectional side view of a drive transmission device that employs a vacuum seal device according to an embodiment. FIG. 2 is an enlarged cross-sectional view of a portion of FIG. 1 . 3 is a cross-sectional view of the vacuum seal device of the embodiment taken along line III-III in FIG. 2. FIG. 3 is an enlarged view of part IV in FIG. 2 .

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a partial cross-sectional side view of a drive transmission device 1 that employs a vacuum seal device 10 according to an embodiment.
The drive transmission device 1 is attached to a part of a partition wall 3 that separates the inside and outside of a vacuum chamber 2 (a room that is kept in a vacuum state). An actuator (transport robot, etc.) (not shown) is installed inside the vacuum chamber 2. The power (rotational force) of the drive transmission device 1 is transmitted to a driven part of the actuator inside the vacuum chamber 2. The actuator receives power from the drive transmission device 1 and operates a moving part (an arm part, etc.) inside the vacuum chamber 2.

The drive transmission device 1 comprises a drive unit 4 and a vacuum seal device 10. The drive unit 4 is arranged on the atmospheric side (outside the vacuum chamber 2). The vacuum seal device 10 transmits the power of the drive unit 4 to an operating device (driven part) within the vacuum chamber 2 while restricting the ingress of atmospheric air into the vacuum chamber 2.

The drive device 4 includes an electric motor 5 that generates a rotational driving force, and a reducer 6 that reduces the rotational force of the motor 5 to a predetermined reduction ratio and outputs it from an output shaft 6a. In the figure, o1 is the central axis of the output shaft 6a.
In the following description, the direction along the central axis o1 is referred to as the "axial direction," and the direction perpendicular to the central axis o1 is referred to as the "radial direction." The atmospheric side of the partition wall 3 in the axial direction is referred to as the "axial outer side," and the opposite side is referred to as the "axial inner side." The radial side toward the central axis o1 is referred to as the "radial inner side," and the opposite side is referred to as the "radial outer side."

In this embodiment, the drive device 4 is composed of the motor 5 and the reducer 6, but the drive device 4 may be composed of only the motor 5. The motor 5 is not limited to an electric type, and may be a pneumatic or hydraulic motor.

Fig. 2 is an enlarged cross-sectional view of the vacuum seal device 10 in Fig. 1. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.
The vacuum seal device 10 comprises a substantially cylindrical housing 11, a rotation transmission member 12, and a seal member 13. The housing 11 is disposed straddling the inside and outside (vacuum side and atmosphere side) of the vacuum chamber 2. The rotation transmission member 12 passes through the housing 11 in the axial direction to transmit rotational power from the atmosphere side (outside of the vacuum chamber 2) to the vacuum side (inside of the vacuum chamber 2). The seal member 13 seals the gap between the housing 11 and the rotation transmission member 12.

The housing 11 includes a first housing 11A that is fixed to the bulkhead 3 while penetrating a portion of the bulkhead 3, and a second housing 11B that is integrally joined to the axially outer end of the first housing 11A. The first housing 11A and the second housing 11B are made of a metal material.

The first housing 11A has a perforated disk-shaped base wall 14 fitted into the through hole 3a (see FIG. 1) of the partition wall 3, and a cylindrical wall 15 protruding axially outward from the base wall 14. The space between the base wall 14 and the through hole 3a of the partition wall 3 is sealed by a seal member 90 (see FIG. 1). A through hole 16 is formed in the radial center region of the first housing 11A, penetrating the base wall 14 and the cylindrical wall 15 in the axial direction. The axial center region 16c of the through hole 16 is formed with a smaller inner diameter than the axial inner region (region on the vacuum chamber 2 side) of the through hole 16. The axial outer region of the through hole 16 is formed with an inner diameter expanded in a stepped manner relative to the axial center region 16c. The axial outer region of the through hole 16 is formed as a seal support portion 17 that supports the seal member 13.

A groove 18 is formed in the first housing 11A. The groove 18 is disposed in a region of the first housing 11A that is radially outside the seal support portion 17. The groove 18 is formed in a substantially C-shape in front view. The groove 18 opens to an end face (one end side in the axial direction) on the axially outer side of the cylindrical wall 15. The groove 18 is formed axially deeper than the region where the seal support portion 17 is formed, and at a sufficient radial height (a radial height sufficiently higher than the radial height of the seal member 13). The groove 18 is closed by an end portion on the axially inner side of the second housing 11B. A space portion surrounded by the groove 18 and the end portion of the second housing 11B constitutes an outer cooling passage 19. A cooling liquid (liquid) is introduced into the outer cooling passage 19 as a cooling fluid.
3, both circumferential ends of the groove 18 are partitioned by a partition wall 76. A groove (not shown) is formed in the axially outer end of the partition wall 76. The groove annularly connects the circumferential surfaces located on the radially inner side of the inner surfaces forming the groove 18 (connecting in the circumferential direction the portions of the groove 18 divided by the partition wall 76).

As shown in FIG. 3, the outer cooling passage 19 is formed in a substantially C-shape. An inlet hole 20a is provided at one circumferential end of the outer cooling passage 19. An outlet hole 20b is provided at the other circumferential end of the outer cooling passage 19. The inlet hole 20a and the outlet hole 20b penetrate the cylindrical wall 15 in the radial direction. A cooling pipe for the cooling liquid is connected to the inlet hole 20a. A discharge pipe for the cooling liquid is connected to the discharge hole 20b. The inlet hole 20a and the outlet hole 20b are arranged at positions close to each other in the circumferential direction on the outer peripheral surface of the cylindrical wall 15. Therefore, the supply pipe and the discharge pipe are concentrated at one location on the outer peripheral surface of the cylindrical wall 15.

As shown in FIG. 2, the second housing 11B has a cylindrical peripheral wall 21 and an end connection portion 22 that is connected to the end of the tubular wall 15.

The end joint 22 is integrally formed at the axially inner end of the peripheral wall 21. The end joint 22 has a joint flange 23 and a blocking portion 24. The joint flange 23 is bolted to the cylindrical wall 15 while being abutted against the end face of the cylindrical wall 15. The blocking portion 24 is formed in an annular shape. The blocking portion 24 blocks the opening of the recessed groove 18. A protrusion 25 having an annular shape in a front view is integrally formed on the inner peripheral edge of the blocking portion 24. The protrusion 25 protrudes from the blocking portion 24 toward the axially inner side. The protrusion 25 is tightly fitted across the peripheral surface and the groove located radially inner among the inner surfaces forming the recessed groove 18. The opening of the recessed groove 18 is blocked by the end joint 22. Reference numeral 91 in FIG. 2 denotes a seal member that seals between the first housing 11A and the second housing 11B at the radially inner position and the outer position of the recessed groove 18.

The case of the reducer 6 is fitted inside the peripheral wall 21. The second housing 11B is fixed to the reducer 6. The space inside the peripheral wall 21 constitutes an inner cooling passage 26 facing the sliding contact portion of the seal member 13. The inner cooling passage 26 is blocked on the axially outer side by the reducer 6. A cooling gas (e.g., cooling air) is introduced into the inner cooling passage 26 as a cooling fluid. An inlet hole 27a for introducing the cooling gas into the inner cooling passage 26 and an outlet hole 27b for discharging the cooling gas from the inner cooling passage 26 are formed at two positions spaced apart in the circumferential direction of the peripheral wall 21.

The inlet hole 27a and the outlet hole 27b are formed at positions spaced approximately 180° apart on the circumference of the peripheral wall 21. As with the outer cooling passage 19, the inner cooling passage 26 may be formed in a roughly C-shape when viewed from the front. In this case, the inlet hole 27a and the outlet hole 27b are formed at positions close to each other on the circumference of the peripheral wall 21. This allows the supply piping and exhaust piping for the cooling gas to be concentrated in one location on the outer circumferential surface of the peripheral wall 21.

The rotation transmission member 12 is composed of a cylindrical metal block with a bottom. The output shaft 6a of the reducer 6 is coupled to the rotation transmission member 12 via a key 28. The rotation transmission member 12 is configured to be able to rotate integrally with the output shaft 6a around the central axis o1. The rotation transmission member 12 has a flange portion 30 and a tubular portion 31. The flange portion 30 is fastened and fixed to the coupling member 29 at the bottom side (axial inner side) of the rotation transmission member 12. The coupling member 29 is connected to the driven part of the actuator in the vacuum chamber 2. The tubular portion 31 protrudes from the root portion of the flange portion 30 toward the axial outer side. The rotation transmission member 12 is inserted into the through hole 16 of the housing 11 (first housing 11A) in a state where it is coupled to the output shaft 6a. The outer peripheral surface of the tubular portion 31 faces the axial center region 16c of the through hole 16 and the seal support portion 17 in the radial direction.

FIG. 4 is an enlarged cross-sectional view of the portion IV in FIG.
4, the seal support portion 17 has an inner peripheral wall 17a that faces the outer peripheral surface of the cylindrical portion 31 in the radial direction, and an end wall 17b that extends radially inward from an axially inner end of the inner peripheral wall 17a. In this embodiment, two seal members 13 are attached to the seal support portion 17 side by side in the axial direction. The seal members 13 seal the gap between the first housing 11A and the outer peripheral surface of the cylindrical portion 31. The two seal members 13 have the same structure.

The seal member 13 includes a cylindrical base 13a, an annular seal portion 13b, and a spring 13c. The base 13a is fitted inside the inner peripheral wall 17a. The seal portion 13b extends radially inward from the axially inner end of the base 13a, and then extends axially outward. The inner peripheral surface of the seal portion 13b is in sliding contact with the outer peripheral surface of the rotation transmission member 12 (tubular portion 31). The portion of the seal portion 13b that is in sliding contact with the outer peripheral surface of the rotation transmission member 12 (hereinafter referred to as the "sliding contact portion") is composed of a multi-stage annular lip portion. The spring portion 13c presses the lip portion of the seal portion 13b against the outer peripheral surface of the rotation transmission member 12.

The main parts of the base 13a and the seal portion 13b of the seal member 13 are formed from a rubber-like elastic material. A core metal 32 (metal member) with a generally L-shaped cross section is embedded in the elastic material. The core metal 32 extends from the seal portion 13b to the base portion 13a. The part of the core metal 32 that extends along the radial direction is exposed to the outside on the axially inner side.

Of the two seal members 13, the seal member 13 located on the axially inner side has the exposed portion of the core metal 32 abutting against the end wall 17b of the seal support part 17 (housing 11). The seal member 13 located on the axially inner side can transfer heat generated at the sliding contact part to the inner peripheral wall 17a of the seal support part 17 through the direct contact part between the core metal 32 and the end wall 17b. The vacuum pressure in the vacuum chamber 2 acts on the seal member 13 located on the axially inner side through the gap between the through hole 16 of the first housing 11A and the outer peripheral surface of the rotation transmission member 12.

Of the two seal members 13, the seal member 13 arranged on the axially outer side faces the inner cooling passage 26 with the sliding contact portion of the seal portion 13b together with the outer peripheral surface of the rotation transmission member 12 (cylindrical portion 31). The axially outer seal member 13 is cooled by the cooling gas flowing through the inner cooling passage 26 together with the outer peripheral surface of the rotation transmission member 12 (cylindrical portion 31).

The drive transmission device 1 operates as follows.
When the motor 5 of the driving device 4 is driven, the rotation of the motor 5 is decelerated by the reducer 6 and then transmitted from the output shaft 6a to the rotation transmission member 12. The rotation transmission member 12 rotates about the central axis o1 while the space between the rotation transmission member 12 and the housing 11 is sealed by two seal members 13. The rotation of the rotation transmission member 12 is also transmitted to the operating device in the vacuum chamber 2 through a coupling member 29.

While the rotation transmission member 12 rotates, cooling liquid is introduced into the outer cooling passage 19, and cooling gas is introduced into the inner cooling passage 26. As a result, the seal support portion 17 is cooled by the cooling liquid flowing in the outer cooling passage 19 on the outer peripheral side of the seal support portion 17. The sliding contact portion of the axially inner seal member 13 is directly cooled by the cooling gas flowing in the inner cooling passage 26 together with the outer peripheral surface of the rotation transmission member 12. Therefore, frictional heat generated in the sliding contact portion of the seal member 13 as the rotation transmission member 12 rotates is removed by the cooling liquid flowing in the outer cooling passage 19 and the cooling gas flowing in the inner cooling passage 26.

As described above, in the vacuum seal device 10 of this embodiment, the cooling fluid (coolant) flows through the outer cooling passage 19 provided in the radially outer region of the seal support part 17. Therefore, heat of the seal member 13 is efficiently removed in a wide region spanning from the atmosphere side to the vacuum side of the seal member 13.
Therefore, when the vacuum seal device 10 of this embodiment is employed, the sealing performance of the seal member 13 can be maintained excellent for a long period of time.

The drive transmission device 1 employing the vacuum sealing device 10 of this embodiment can efficiently remove heat from the sealing member 13, and therefore can transmit the power of the drive device 4 to the operating device (driven part) in the vacuum chamber 2 while maintaining good sealing performance of the sealing member 13 for a long period of time.

In the vacuum seal device 10 of this embodiment, an inner cooling passage 26 is provided in an atmospheric side region of the housing 11 facing the outer circumferential surface of the rotation transmission member 12 and the sliding contact portion of the seal member 13. Therefore, the vicinity of the sliding contact portion, which is prone to heat generation, can be efficiently cooled by the cooling fluid (cooling gas) flowing through the inner cooling passage 26.
Therefore, the vacuum seal device 10 of this embodiment can cool a wide area spanning from the atmosphere side to the vacuum side of the seal member 13 by the cooling fluid flowing through the outer cooling passage 19. The seal device 10 can directly and efficiently remove heat from the sliding contact portion of the seal member 13, which generates the most heat, by the cooling fluid flowing through the inner cooling passage 26.

In the vacuum seal device 10 of this embodiment, a cooling liquid is introduced as a cooling fluid into the outer cooling passage 19, and a cooling gas is introduced as a cooling fluid into the inner cooling passage 26. Therefore, in the outer cooling passage 19, which does not directly face the sliding contact portion of the seal member 13, the heat of the seal member 13 can be efficiently removed by the cooling liquid (liquid) that has a high heat absorption efficiency from the heat absorption target. In the inner cooling passage 26 facing the sliding contact portion of the seal member 13, by introducing a gas that is not likely to become high pressure when flowing, it is possible to efficiently remove the heat of the sliding contact portion while suppressing unnecessary deformation of the seal member 13 and suppressing the intrusion of the cooling fluid from the sliding contact portion to the vacuum side.

In the vacuum seal device 10 of this embodiment, multiple seal members 13 are arranged along the axial direction between the seal support portion 17 of the housing 11 and the outer peripheral surface of the rotation transmission member 12. Therefore, when the vacuum seal device 10 of this embodiment is adopted, the multiple seal members 13 more reliably restrict the inflow of air into the vacuum side, and the seal member 13 on the axial inner side, where heat is likely to accumulate, can be reliably cooled by the cooling fluid flowing through the outer cooling passage 19.

The seal member 13 used in the vacuum seal device 10 of this embodiment includes a base 13a fixed to the seal support portion 17 of the housing 11, and an annular seal portion 13b extending radially inward from the base 13a and slidingly contacting the outer circumferential surface of the rotation transmission member 12. A core metal 32 is embedded in the rubber-like elastic material constituting the base 13a and the seal portion 13b so as to straddle from the seal portion 13b to the base 13a. Therefore, the heat of the seal portion 13b, which generates heat by slidingly contacting the outer circumferential surface of the rotation transmission member 12, can be efficiently transferred to the seal support portion 17 of the housing 11 via the metal core metal 32. Therefore, when the vacuum seal device 10 of this embodiment is adopted, the heat generated at the sliding contact portion of the seal member 13 can be efficiently removed by the cooling fluid flowing through the outer cooling passage 19.

In the vacuum seal device 10 of this embodiment, the metal core 32 of the seal member 13 is in direct contact with the housing 11. This allows heat generated at the sliding contact portion of the seal member 13 to be dissipated to the seal support portion 17 more efficiently.

In the vacuum seal device 10 of this embodiment, the radially inner end of the end wall 17b is positioned close to the outer circumferential surface of the rotation transmission member 12. The core metal 32 of the seal member 13 is in surface contact with the end wall 17b. This allows heat generated at the sliding contact portion of the seal member 13 to be dissipated to the seal support portion 17 more efficiently.

In the vacuum seal device 10 of this embodiment, the outer cooling passage 19 is surrounded by the groove 18 of the first housing 11A and the second housing 11B. Therefore, the outer cooling passage 19 arranged in the radial outer region of the seal support part 17 can be easily and accurately formed by cutting or the like. The second housing 11B is formed with a protrusion 25 so as to be continuous with the peripheral wall 21 that constitutes a part of the inner cooling passage 26. The protrusion 25 is tightly fitted into the radial inner region of the groove 18 of the first housing 11A. Therefore, leakage of the cooling fluid between the outer cooling passage 19 and the inner cooling passage 26 can be more reliably restricted.

The present invention is not limited to the above-described embodiment, and various design modifications are possible without departing from the spirit and scope of the present invention.
For example, in the above embodiment, a pair of seal members 13 are arranged between the seal support portion 17 of the housing 11 and the outer peripheral surface of the rotation transmission member 12, but the number of seal members 13 is not limited to two and may be three or more.
In the above embodiment, a liquid is introduced as a cooling fluid into the outer cooling passage 19, and a gas is introduced as a cooling fluid into the inner cooling passage 26, but either a liquid or a gas may be introduced into both cooling passages. Alternatively, a gas may be introduced into the outer cooling passage 19, and a liquid may be introduced into the inner cooling passage 26.

1...drive transmission device, 2...vacuum chamber, 3...partition, 4...drive device, 10...vacuum seal device, 11...housing, 11A...first housing, 11B...second housing, 12...rotation transmission member, 13...sealing member, 13a...base, 13b...sealing portion, 17...seal support portion, 17a...inner circumferential wall, 17b...end wall, 18...groove, 19...outer cooling passage, 21...circumferential wall, 25...protrusion, 26...inner cooling passage.

Claims (8)

a housing arranged across a vacuum side, which is an inside of the vacuum chamber, and an atmosphere side, which is an outside of the vacuum chamber;
a rotation transmission member that is disposed to penetrate the housing and rotates about a central axis to transmit rotational power from the atmosphere side to the vacuum side;
a seal member that is disposed in sliding contact with an outer peripheral surface of the rotation transmission member and seals a gap between the housing and the rotation transmission member,
The housing includes a seal support portion that supports the seal member,
an outer cooling passage through which a cooling fluid flows is formed in a region of the housing that is located radially outward from the seal support portion ;
The housing has an inner cooling passage through which a cooling fluid flows,
The inner cooling passage faces the rotation transmission member and a sliding contact portion of the seal member that contacts the rotation transmission member from the atmosphere side . A liquid is introduced into the outer cooling passage as the cooling fluid,
2. The vacuum seal device according to claim 1 , wherein a gas is introduced into the inner cooling passage as the cooling fluid. 3. The vacuum seal device according to claim 1, wherein a plurality of the seal members are disposed between the housing and the rotation transmission member along the axial direction of the rotation transmission member. The sealing member is
A base portion fixed to the seal support portion;
A vacuum seal device as described in any one of claims 1 to 3, comprising an annular seal portion extending radially inward from the base and in sliding contact with the outer peripheral surface of the rotation transmission member, and a core metal embedded so as to span from the seal portion to the base. The vacuum seal device according to claim 4 , wherein the metal core is in contact with the housing. The seal support portion is
an inner circumferential wall facing an outer circumferential surface of the rotation transmission member;
an end wall extending radially inward from one axial end of the inner circumferential wall,
6. The vacuum seal device according to claim 5 , wherein the metal core is in contact with the end wall. The housing includes:
a first housing having a recessed groove that opens to one end side in the axial direction;
a second housing that closes an opening of the recessed groove and constitutes the outer cooling passage together with the recessed groove,
The second housing includes:
A peripheral wall that constitutes a part of the inner cooling passage;
The vacuum seal device according to claim 1 or 2 , further comprising a protrusion provided at one end of the peripheral wall and tightly fitted into at least a radially inner surface of the inner surface forming the groove. A drive unit disposed on the atmosphere side, that is, outside the vacuum chamber;
a vacuum seal device that transmits power of the drive device to a driven part disposed on the vacuum side inside the vacuum chamber and prevents air from entering the vacuum chamber,
The vacuum seal device is
a housing disposed across the vacuum side and the atmosphere side of the vacuum chamber;
a rotation transmission member that is disposed to penetrate the housing and rotates about a central axis to transmit rotational power from the driving device to the driven part;
a seal member that is disposed in sliding contact with an outer peripheral surface of the rotation transmission member and seals a gap between the housing and the rotation transmission member,
The housing includes a seal support portion that supports the seal member,
an outer cooling passage through which a cooling fluid flows is formed in a region of the housing that is located radially outward from the seal support portion ;
The housing has an inner cooling passage through which a cooling fluid flows,
The inner cooling passage faces the rotation transmission member and a sliding contact portion of the seal member that contacts the rotation transmission member from the atmosphere side .

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